Filling machine for containers

ABSTRACT

A filling nozzle for effecting the controlled filling of a container such as a bottle with liquid and which includes a center filling tube or stem for directing liquid into the container and an outer sleeve-like element for controlling the opening and closing of the filling tube and defining an annular passage around the filling tube to enable air or other container gas to escape from the container during the filling operation. According to the invention, the sleeve-like element is maintained under a vacuum and a liquid draw-back tube is mounted axially within the lower end of the filling tube to communicate the container with the gas escape passage following the termination of the main filling flow of liquid thereto for the purpose of dropping the liquid level in the container to an exact, predetermined final position.

United States Patent [191 Fechheimer FILLING MACHINE FOR CONTAINERS [76] Inventor: Paul R. Fechheimer, Worcester,

Mass.

[22] Filed: Sept. 11, 1972 [21] Appl. No.: 287,805

Related US. Application Data [62] Division of Ser. No. 85,442, Oct. 30, 1970,

abandoned.

[52] US. Cl. 141/119, 141/181- [51] Int. Cl. B65b 3/24 [58] Field of Search 141/4-8, 37,

[5 6] References Cited UNITED STATES PATENTS 3,097,671 7/1963 Bonnetti et a1. 141/116 in] 3,834,430 Sept. 10, 1974 Primary ExaminerHouston S. Bell, Jr.

Attorney, Agent, or Firm-John K. Crump {57] ABSTRACT A filling nozzle for effecting the controlled filling of a container such as a bottle with liquid and which includes a center filling tube or stem for directing liquid into the container and an outer sleeve-like element for controllingtlYe opening and closing of the filling tribe and defining an annular passage around the filling tube to enable air or other container gas to escape from the container during the filling operation. According to the invention, the sleeve-like element is maintained under a vacuum and a liquid draw-back tube is mounted axially within the lower end of the g filling tube to communicate the container with the gas escape passage following the termination of the main filling flow of liquid thereto for the purpose of dropping the liquid level in the container to an exact, predetermined final position.

1 Claim, 3 Drawing Figures PAIENIEB SEPI 01914 SHEET 1 OF 2 FILLING MACHINE FOR CONTAINERS Thisapplication is a division of US. patent applica tion SerQNo. 85,442, filed Oct. 30, 1970, now abandoned.

This invention relates to a container filling machine still nature as opposed to liquids such as carbonated soft drinks and beer which contain large amounts of dissolved gas and which are relatively unstable.

Various forms of filling machines have been devel- I oped and put in use over the years for carrying out the filling of containers with' so-called still liquids, and reference is made to US. Pat. Nos. 2,660,357 to Fechheimer, 3,037,536 to Fechheimer et al., and 3,195,585 also to Fechheimer for typical examples of these prior filler constructions.

While for the most part commercially satisfactory and acceptable, these prior devices were not particularly well adapted to the handling of more than a limited number of difi'erent types of containers and, in many instances, in operating these prior devices with containers of a style or type other than that for which the machine was specifically designed, it was difiicult to attain a high degree of filling accuracy in the containers and/or to maintain a satisfactory level of operational efficiency. Also, in many of these priorfillers, such change parts and modifications as were provided to enable the successful, accurate filling of differing types and/or styles of containers in the machine were not readily susceptible of being incorporated therein with the result that the changing of the filler from one run of container to another often entailed considerable down time and corresponding loss of production.

The instant invention is directed to an improved nozzle assembly for use in filler machines of the general type mentioned and which is particularly well adapted to permit the successful, rapid and accurate filling of containers of widely differing size and shape with various liquids.

The filling nozzles in accordance with the invention include a filling tube or stem arranged axially within a liquid fill height control element in the form of a vacuum tube and movable axially of the vacuum tube upon the lowering of the nozzle to a sealed, filling position relatively of a container to remove an annular sealing means in the lower end of the stem from the end of the vacuum tube whereby to commence a filling flow of liquid to the container. The filling stem is retractable into the vacuum tube to re-engage the sealing means with the vacuum tube and thereby terminate liquid flow to the container generally at the point in the filling cycle where the liquid level is coincident with the lower end of the vacuum tube.

According to this invention, a liquid draw-off tube is mounted axially within the filling stem for communicating the container with the vacuum tube following the retraction of the filling stem into the vacuum tube so as to permit liquid to be drawn out of the container from above the level determined by the vacuum tube to provide more exact, accurate control of the liquid level attaining in the containers being handled in the filler machine.

The nozzles may be controlled for movement relatively of the containers by a conventional cam and follower means, with the cam controlling the retraction of the nozzles from the container being provided, for purposes of the invention, with an intermediate position for holding the nozzle in-a partially retracted position to the container to enable liquid to be removed from the container through the draw-off tube to attain the exact liquid level desired in the finally filled container.

The draw-off tube is of further advantage in that it prevents liquid from dripping onto the container during the retraction of the nozzles or heads, thereby preventing spoilage of any labels which may be present on the container andotherwise preserving the cleanliness and attractiveness of the finally filled container.

The foregoing objects and advantages, together with others, will appear hereinafter or become apparent to the skilled worker in the art to which the invention relates, are accomplished by the exemplary embodiments of the invention which are illustrated in the accompanying drawings.

In the drawings:

FIGS. 1A through lC illustrate successive stages in the withdrawal from a container being filled with liquid of one of the novel filling nozzles of the invention showing the manner in which the draw-off tube functions to maintain the liquid at a predetermined level in the container; and FIG. 1B is an enlarged, longitudinal sectional view of the lower tip portion of a filling nozzle of the invention, showing the relationship of the O-ring sealing member to the lower end of the outer vacuum tube.

Referring now to the drawings, the reference numeral (330) depicts a filling nozzle formed according to the invention and which, while not shown, normally would be mounted, along with a plurality of identical such nozzles, in the upper rotary head portion of a filler machine to carry out the automatic, rapid filling of containers such as bottles (B). A detailed showing of a filler machine of the type with which the nozzle may be employed is contained in a copending application of applicant, more particularly identified as United States patent application Ser. No. 287,695, filed Sept. 11, 1972, and reference may be made to such application for a more complete showing and description of a filler suited to receive a nozzle of the invention. Generally speaking, the nozzle includes a center tube or stem (332) adapted to be received axially within the upper end portion of a bottle or other container upon the nozzle and container being moved relatively into filling relation with one another. The lower end or tip of stem (332.) is closed by a special, extended plug-like element (336) to be described in more detail hereinafter with the stem itself being provided with a series of relatively large side openings (338) immediately above plug-like element (336) foraccommodating liquid flow into a container from the stem. The ends of plug (336) are expanded radially as respects the stem to which it is attached with the lower expanded portion of the plug being providedv with a circumferentially extending groove (340) which seats an O-ring (342), the function of which will become readily apparent hereinafter.-

The filling tube or stem (332) has further mounted thereon a vertically slidable vacuum body and tube assembly indicated as a whole in the drawings by the reference numeral (344). Assembly (344) comprises an enlarged, cylindrical vacuum body (346) having an axially extending bore (348) for receiving the tube or stem (332) and which is open to an enlarged recess (350) in the upper end of the body, as shown. A separate cover (352) is provided the vacuum body, being releasably connected thereto by another of theC-type clamps fitting over and between mating beveled flanges on the cover and on the upper end of the body. The vacuum body (346) is slidingly engaged with the filling tube or stem through structure which includes a centrally sliding seal (354) which fits in the'recess (350) with the inner lip-like edge (356) of the split seal segments engaging the tube (332). An O-ring (358) is fitted between the mating outer edge portions of the seal segments to seal the body itself to the cover (352) when the C-clamp is in place.

The axial bore (348) of vacuum body (346) communicates laterally via a port (362) in the body with a suitable source of vacuum, not shown.

Mounted axially to the lower end of the vacuum body (346) is a vacuum tube (364) of a slightly larger inside diameter than the outside diameter of the filling tube or stem (332).

The vacuum tube (364) terminates above the free, lower end of the filling stem (332) and is normally maintained by the weight of the combined vacuum body and tube assembly v(344) or by a spring in an axially lower slide position on the stem with the tip of the tube in an engaged closed position against the aforesaid O-ring (342) carried in the plug (336) in the stem. The O-ring (342) as thus positioned provides a valve action between the liquid and vacuum tubes (332) and (364) respectively, whereby to control the opening and closing of these members and thereby control the flow of liquid through the nozzle assemblies. The O-ring (342) further serves as a retainer for holding the vacuum body and tube assembly (344) onto the liquid tube or stem and to this end the O-ring is sized, as respects its inside diameter, relatively of the groove (340) soas to require some stretching of the O-ring to enable its installation, thereby to insure the O-ring being retained tightly on the plug. At the same time, however, the O- ring should not be stretched to the extent as would preclude the relative ready removal of the O-ring from the groove when O-ring replacement is required or when removal of the vacuum tube from the filling stem is desired.

The outside diameter of the O-ring must, of course, be related to the vacuum tube diameter in a way as will produce the aforesaid closing engagement of the lower end of the vacuum tube by the O-ring when the vacuum tube is in the normal, lower axial slide position on the filling stem. Over and above this, however, the vacuum tube (364) itself generally will be made as large as possible in outside diameter while still providing clearancev with the sides of the containers when inserted axially thereinto, allowing for the normal tolerances in container neck openings which have been established in the container industry, and for this reason it is preferred that O-ring (342) be further dimensioned such that its outside diameter, as measured with the O-ring installed in the groove and in a stretched conditiomis at a value which lies between the inside and outside diameters of the vacuum tube.

The O-ring as thus dimensioned and positioned on the filling stem acts further to shroud the end of the vacuum tube from the containers during the lowering of the nozzle assemblies to filling positions thereto. This is desirable in that it protects the sealing edge of the vacuum tube from possible damage in the event ,of any misalignment between the containers and nozzles. Such damage is to be avoided, of course, as it would invariably impair the sealing action between the O-ring and the vacuum tube and cause a malfunctioning of the nozzle assemblies.

- The filling head portions of nozzle assemblies (330) are each further provided with a resiliently deformable disc-like member (368) which is designed to seal the container to the nozzle assemblies when the latter are in filling relation to the containers. Disc member or seal (368), and which. in the usual instance is composed of soft, resilient material such as rubber for example, is carried on vacuum tube (364) and is preferably backed by a stiffener washer (370) to prevent the seal from defleeting in its unsupported section when in engagement with a container. The lower face of disc (368) may be provided with a Teflon liner if desired so as to afford the seal a measure of protection against the action of the product being filled and/or to minimize adhesion between the seal and the container at the point in the filling cycle when the nozzle assemblies .are retracted from the containers.

The seal itself is in frictional sliding engagement with vacuum tube (364) through O-ring means or other conventional sealant means carried in stop or seat thereon for the sealing member (368). Spacer tube (372) preferably takes the form of a longitudinally split, C-section type plastic extrusion such as the type commonly used as wear strips on conveyor guide rails, for example, and which has sufficient resiliency as will permit its ready application to and removal from the vacuum tube by manual means. When this tube is in place, the container seal 368) is adjusted axially of the vacuum tube to a position against the lower, free end of the tube whereby to provide anexact setting of the seal on the tube (364) and a corresponding exactness in the length of the portion of the vacuum tube which will enter the container when the latter is in filling position against the seal. A number of tubes of different predetermined lengths generally may be provided for use where containers of varying heights are to be handled in a given filler machine so that when changing to a run of containers of any given height the set of spacer tubes which have been designed for such containers may be readily assembled onto the vacuum tubes.

In the normal operation of the nozzle assembly, the nozzle and a container such as a bottle are moved relatively toward one another by any suitable means with the tip portions of filling stem (332) and vacuum tube (364) entering the mouth of the container and progressing thereinto as a unit to the point where the mouth of the container engages the container sealing member (368). At such time, the nozzle assemblies will not have completed full movement relatively toward the con- .tainers and as a result thereof the filling stem (332) will move or penetrate progressively further into the container by slide movement relatively of the now fixed vacuum tube (364) thereby causing the O-ring (342) to unseat from the end of the vacuum tube to open the filling stem (332) for filling action. At this point, and if it be assumed that the liquid supply is elevated sufficiently to the nozzles provide gravity flow of liquid to the containers and that a vacuum is maintained in the tube (364), air will start to be exhausted from thecontainer through vacuum tube (364) concurrently as liquid commences to fill the container by gravity flow thereinto through the filling stem (332) and the filling ports (338) in plug (336). Air and liquid interchange in the container continue in the manner indicated to cause the container to progressively fill with liquid to the level at which the liquid closes the end of the vacuum tube (364). Upon this occurrence, liquid flow to the container is abruptly slowed and only so much additional liquid is admitted to the container from the filling stem as will result in the air in the head space of the container compressing to the point where the head space pressure balances the head on the liquid and to replace the slight amount of liquid as will be drawn out of the container through the vacuum tube. After the liquid has risen to above the end of the vacuum tube and liquid flow to the container is interrupted, the nozzle assembly (10) is caused to retract relatively from the container by suitable automatic means such as a cam and follower as described in more detail in the aforesaid application Ser. No. 287,695, filed Sept. 11, 1972. leading or forward edge (292a) of cam plate (292) and which is angled upwardly in the abrupt fashion as described for the trailing edge (292b) of the cam plate. In this withdrawal or retraction of the nozzle as sembly, the vacuum tube (364) remains stationary to the container during the brief period which is required for O-ring (342) on the filling stem (332) to engage the tip of the vacuum tube following which point the tubes (332) and (364) move as a unit out of the container.

level in the container will be slightly below the level ini-- tially produced therein. Generally, the liquid drop-off from one container to the next will be substantially constant and it is only necessary then to attain a final, desired level of liquid in any particular type of container to determine for such container the axial position on the vacuum tube of the sealing member which will provide the initial fill height of liquid in the con-' tainer as will give the desired final liquid level when the plug is retracted fully from the container. Once this setting is determined, a set of spacer tubes of the requisite length may then be prepared so that in running this type of container the tubes could be employed with the nozzle assemblies to give the control desired over liquid fill height.

While the control of liquid level as thus achieved is for the most part adequate, in some instances it is desired to attain a very precise control of the liquid level in the containers and for this and other reasons as well, the filling head as above described is altered to include a relatively small diameter draw-off tube (374) in the center of the filling stem or tube (326). This draw-off tube has an angular upper end portion (376) which extends through and is secured in a flush position against and open communication between the tube (374) and the annular clearance defined between the liquid and vacuum tubes. The lower end of draw-back tube (374) is supported axially in the lower end of the filling stem by the aforesaid plug (336) which is bored axially as indicated at (378) to receive the tube (374), the latter being cemented to the plug in seated relation against an intermediate shoulder in the bore by a suitable adhesive to positively hold the tube in the plug. The plug as is best brought out in FIG. 1d is characterized by the provision thereon of a relatively small diameter, elongated tip or extension (380) which carries the tube to a desired length below the filling stem.

Tube (374) is designed to draw liquid out of the container above a predetermined level therein after filling has been completed and upon the nozzle assembly being drawn partially from the container and, in order to achieve this the filler embodying the nozzle would be provided with a suitable auxiliary cam (not shown) to maintain the nozzle assembly as a whole in a partially retracted position to the containers following completion of the main portion of the filling cycle.

Such auxiliary cam or other means would normally be adjusted or set vertically to the filler machine so-as to cause the draw-back tube (374) of the nozzle assemblies to be retracted partially from the container after the liquid has risen to and above the level of the vacuum tube terminus whereby to permit so much of an additional increment of liquid to be drawn out of the container through the tube as will drop the liquid level in the container to the exact point or position desired therein. It is essential for this liquid draw-back action that the liquid and vacuumtubes be closed by the O- ring valve (342) in the filling stem plug (336) and also that the container sealing member (368) of the nozzle assembly be disengaged from or raised above the mouth of the container whereby to provide atmospheric pressure in the container above the liquid level therein and it will be understood, therefore, that the extension (380) of the filling stem plug 336) must be of a sufficient axial length as to enable the closing of the nozzle assembly and the lifting of the container seal from the container during the retraction of the extension (380) from its normal axial position in the container to the intermediate position therein through the described co-action of the auxiliary cam (382) with the cam follower roller (290).

With this draw-off tube, the liquid level will be finally established in the container at a level slightly below the lower terminus of the stem tip extension (380). This is as a result of the water spout effect, and the exact distance of the fill height below the tip will depend upon the diameter of the draw-off tube and the level of the wall of the filling stern in a manner establishing free vacuum established in the container. The water spout effect may be minimized by providing the bottom of the extension with an internal flare whereby to reduce the velocity of air flow thereinto.

Generally, in using the draw-back tube, the spacer tube (372) for the container sealing member (368) is provided a length which is slightly reduced from that which would be utilized with a filling head of standard 7 construction so as to insure a filling of the container to a level above that which is finally desired in the container when the filling stem and main vacuum tube are in partially retracted or raised positions to the container. This, of course, is to prevent underfills or shorts in the containersand to assure liquid fill height constancy from container to container in using this modified form of nozzle assembly.

This control of liquid level is attained at some sacrifree in the operating output or capacity of the filler machine since some minimum period of time and cam length are necessarily required to insure that the liquid level in the container is dropped by the draw-back tube the necessary full amount. As an example of the effect of incorporating such an auxiliary cam into a filler machine, reference is made to an actual instance wherein the auxiliary cam had an arcuate length of approximately 45 and wherein the filling period as measured from the time at which the container sealing member of any particular nozzle assembly engages and effects a sealing of the container to the time or period at which the seal of such nozzle assembly is removed from the container was 17 percent less than thefilling time attainable with a head of standard construction.

The draw-off tube (374) has the collateral advantage of giving positive drip control to the nozzle assemblies during retraction from the containers and this is effective to prevent such things as label spoilage, product waste, package unsightliness, etc., due to liquid dripping onto the exterior of the containers during the filling cycle. On the other hand, with this optional feature vacuum loss will occur through the nozzle assemblies during the portion of the filling cycle in which the nozzles are in retracted positions to the filler table. Further loss of vacuum will be experienced whenever there is an absence in the filler of a full complement of containers on the filler table. Accordingly, it is generally necessary when using this modified type of filling head to employ a vacuum pump of a somewhat greater capacity than normally necessary. It is possible, too, with this type of head to utilize a vacuum zone control system such as that shown and described in U.S. Pat. No. 2,785,341, for example, to prevent vacuum loss through the nozzle assemblies under the enumerated conditions. Such a zone control mechanism could be supplementary to, or in lieu of the higher capacity vacuum pump, as desired.

From the above, it can be seen that the invention provides an improved filling nozzle for use in a container filling machine and which in addition to other features and advantages includes a highly novel arrangement for attaining extreme filling accuracy in the filling of the containers to-a predetermined or desired level and for attaining, as a corrollary thereto, control over the liquid dripping from the assemblies upon retraction'from the containers when filling is completed.

I Various modes of carrying out the present invention are contemplated as being within the scope of the following claims particularly pointing out and distinctly claiming the subject-matter regarded as the nature of the invention.

' lclaim:

1. A vacuum-type, container filling machine which comprises, a rotary filler table for supporting the containers during filling, a series of individual filling nozzles mounted radially above said table for movement relatively between raised, inactive positions to the containers when in filling positions on said table and lowered, filling positions thereto, said filling nozzles each including an inner liquid tube, an outer vacuum tube axially slidable carried on said liquid tube, valve means carried on the lower end of the liquid tube and acting between the lower ends of said liquid and vacuum tubes to control the opening and closing of the tubes to flow, said valve means closing said tubes to flow when the vacuum tube is in a first, lowered axial slide position on said liquid tube and said vacuum tube normally disposedin such first, lowered axial position to the liquid tube, a sealing member carried by said vacuum tube and engageable with a container upon the filling nozzles being lowered relatively toward a filling position with respect thereto, said sealing member acting on the container during the further lowering of the filling nozzles to the containers and during the subsequent raising of the nozzles from filling positions to cause the valve means to initially disengage from the end of the vacuum tube whereby to open the liquid and vacuum tubes to flow and to subsequently re-engage the end of the vacuum tube to close the tubes to flow, a secondary vacuum tube supported centrally within the liquid tube with the upper end of the tube opening through the side of the liquid tube to the vacuum tube, said secondary vacuum tube having an elongated tip extending from below the liquid tube and vacuum tube to maintain an open passage between the vacuum tube and a container upon the valve means reengaging the end of the vacuum tube during the initial raising of the nozzles from filling positions to the containers, and means for maintaining the filling nozzles in a partially raised position to the containers following the filling thereof to permit such liquid as is present in the containers above the terminus of the extension of said secondary vacuum tube to be drawn from the container. 

1. A vacuum-type, container filling machine which comprises, a rotary filler table for supporting the containers during filling, a series of individual filling nozzles mounted radially above said table for movement relatively between raised, inactive positions to the containers when in filling positions on said table and lowered, filling positions thereto, said filling nozzles each including an inner liquid tube, an outer vacuum tube axially slidable carried on said liquid tube, valve means carried on the lower end of the liquid tube and acting between the lower ends of said liquid and vacuum tubes to control the opening and closing of the tubes to flow, said valve means closing said tubes to flow when the vacuum tube is in a first, lowered axial slide position on said liquid tube and said vacuum tube normally disposed in such first, lowered axial position to the liquid tube, a sealing member carried by said vacuum tube and engageable with a container upon the filling nozzles being lowered relatively toward a filling position with respect thereto, said sealing member acting on the container during the further lowering of the filling nozzles to the containers and during the subsequent raising of the nozzles from filling positions to cause the valve means to initially disengage from the end of the vacuum tube whereby to open the liquid and vacuum tubes to flow and to subsequently re-engage the end of the vacuum tube to close the tubes to flow, a secondary vacuum tube supported centrally within the liquid tube with the upper end of the tube opening through the side of the liquid tube to the vacuum tube, said secondary vacuum tube having an elongated tip extending from below the liquid tube and vacuum tube to maintain an open passage between the vacuum tube and a container upon the valve means reengaging the end of the vacuum tube during the initial raising of the nozzles from filling positions to the containers, and means for maintaining the filling nozzles in a partially raised position to the containers following the filling thereof to permit such liquid as is present in the containers above the terminus of the extension of said secondary vacuum tube to be drawn from the container. 